Messages in this thread | | | Date | Mon, 22 Nov 2010 09:07:10 +0100 | From | Ingo Molnar <> | Subject | Re: -tip tree resume fail, bisect to 5bd5a45(x86: Add NX protection for kernel data) |
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* Lin Ming <ming.m.lin@intel.com> wrote:
> Hi, all > > Current -tip tree(92c883a) fail to resume after suspend to mem. > Bisect to commit 5bd5a45(x86: Add NX protection for kernel data). > > commit 5bd5a452662bc37c54fb6828db1a3faf87e6511c > Author: Matthieu Castet <castet.matthieu@free.fr> > Date: Tue Nov 16 22:31:26 2010 +0100 > > x86: Add NX protection for kernel data > > > I did some debug and found the regression is caused by below line. > > - set_memory_nx(rodata_start, (end - rodata_start) >> PAGE_SHIFT); > + set_memory_nx(rodata_start, (kernel_end - rodata_start) >> PAGE_SHIFT); > > In my machine, > rodata_start=0xffffffff81a00000, end=0xffffffff81e00000, kernel_end=0xffffffff82200000 > > Without this commit, kernel page table dumps > > ---[ High Kernel Mapping ]--- > .... > 0xffffffff81a00000-0xffffffff81c00000 2M ro PSE GLB NX pmd > 0xffffffff81c00000-0xffffffff81d91000 1604K ro GLB NX pte > 0xffffffff81d91000-0xffffffff81e00000 444K ro GLB NX pte > 0xffffffff81e00000-0xffffffff82000000 2M RW PSE GLB x pmd > 0xffffffff82000000-0xffffffff8200c000 48K RW GLB x pte > 0xffffffff8200c000-0xffffffff82100000 976K RW GLB x pte > 0xffffffff82100000-0xffffffff82200000 1M RW GLB x pte > ..... > > With this commit, kernel page table dumps > > ---[ High Kernel Mapping ]--- > .... > 0xffffffff81a00000-0xffffffff81c00000 2M ro PSE GLB NX pmd > 0xffffffff81c00000-0xffffffff81d91000 1604K ro GLB NX pte > 0xffffffff81d91000-0xffffffff81e00000 444K ro GLB NX pte > 0xffffffff81e00000-0xffffffff82000000 2M RW PSE GLB NX pmd > 0xffffffff82000000-0xffffffff8200c000 48K RW GLB NX pte > 0xffffffff8200c000-0xffffffff82100000 976K RW GLB NX pte > 0xffffffff82100000-0xffffffff82200000 1M RW GLB NX pte > ..... > > The only difference is 0xffffffff81e00000(end) to 0xffffffff82200000(kernel_end) is set to NX. > > I guess this range code is used by resume wakeup code. So setting it to NX causes problem. > > Any idea?
Yeah, the resume area is a trampoline, it needs to be executable.
Thanks,
Ingo
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